Yeah I'm not sure about Alex.
I do think overtly sexy puts him off, and bizzarely my daughter house shares with a doctor and he's the same, totally straight, but he wants limited make up and a girl who dresses demurely and he's a young attractive chap. They all take the piss out him, but I suspect something similar with Alex, he's looking for sporty, relatively demure kind of female. I think alexsandra going overtly sexy into hideaway didn't do it for him and he felt pressured and turned off.
As much as we might find it odd, some guys really don't like overtly sexy even though they are straight. Even though alexsandra looked phenomenal I think it had the opposite affect on him that she planned.